Numeric keypads on mobile telephones are generally used for dialing a phone number. With the proliferation of wireless coverage and data communication services for mobile phones, many users can now communicate by way of sending text messages (i.e., texting).
Referring to FIG. 1, a standard numeric keypad has at least 10 numeric keys, such that there is a one-to-one relationship between each key on the numeric keypad and a digit in the range from 0 to 9. To allow a person to send a text message, the letters of alphabet are displayed on each key. There is no one-to-one assignment, however, between the letters of the alphabet and the numeric keys on a numeric keypad, because the number of alphabet letters in a language is more than 10. Thus, more than one letter of the alphabet has to be assigned to each key in order to enable a full alphabetic keypad.
The problem associated with the design of an alphabetic keyboard on the 10 keys of a numeric keypad is that editing a text message, in most cases, requires a person to strike a key on the numeric keypad more than once in order to select a single alphabetic letter. Referring to FIGS. 1 and 2, for example, where alphabet letters “a”, “b”, and “c” are assigned to a numeric key for the number 2, a person may have to press the number 2 key three times just to enter a single letter “c”.
FIG. 2 illustrates the number of key strokes associated with the letters of the English alphabet according to a standard mapping to a numeric keypad. As shown, the number of strokes for most letters is larger than one, requiring a user to interact excessively with the keypad in order to input a text message. The above-noted problem further leads to user frustration and errors. Methods and systems are needed than can overcome said problems.